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#/*++
#
#Copyright (c) 2006, Intel Corporation
#All rights reserved. This program and the accompanying materials
#are licensed and made available under the terms and conditions of the BSD License
#which accompanies this distribution. The full text of the license may be found at
#http://opensource.org/licenses/bsd-license.php
#
#THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
#WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
#
#Module Name:
#
# EfiSetMem.asm
#
#Abstract:
#
# This is the code that supports IA32-optimized SetMem service
#
#--*/
#include "EfiBind.h"
#---------------------------------------------------------------------------
.686:
#.MODEL flat,C
.mmx:
.code:
#---------------------------------------------------------------------------
.globl ASM_PFX(EfiCommonLibSetMem)
#VOID
#EfiCommonLibSetMem (
# IN VOID *Buffer,
# IN UINTN Count,
# IN UINT8 Value
# )
#/*++
#
#Input: VOID *Buffer - Pointer to buffer to write
# UINTN Count - Number of bytes to write
# UINT8 Value - Value to write
#
#Output: None.
#
#Saves:
#
#Modifies:
#
#Description: This function is an optimized set-memory function.
#
#Notes: This function tries to set memory 8 bytes at a time. As a result,
# it first picks up any misaligned bytes, then words, before getting
# in the main loop that does the 8-byte clears.
#
#--*/
ASM_PFX(EfiCommonLibSetMem):
pushl %ebp
movl %esp, %ebp
subl $0x10, %esp # Reserve space for local variable UINT64 QWordValue @[ebp - 10H] & UINT64 MmxSave @[ebp - 18H]
pushl %ebx
pushl %edi
movl 0xC(%ebp), %edx # Count
testl %edx, %edx
je _SetMemDone
pushl %ebx
movl 8(%ebp), %eax # Buffer
movb 0x10(%ebp), %bl # Value
movl %eax, %edi
movb %bl, %bh
cmpl $256, %edx
jb _SetRemindingByte
andb $0x7, %al
testb %al, %al
je _SetBlock
movl %edi, %eax
shrl $3, %eax
incl %eax
shll $3, %eax
subl %edi, %eax
cmpl %edx, %eax
jnb _SetRemindingByte
subl %eax, %edx
movl %eax, %ecx
movb %bl, %al
rep
stosb
_SetBlock:
movl %edx, %eax
shrl $6, %eax
testl %eax, %eax
je _SetRemindingByte
shll $6, %eax
subl %eax, %edx
shrl $6, %eax
movw %bx, -0x10(%ebp) # QWordValue[0]
movw %bx, -0x10+2(%ebp) # QWordValue[2]
movw %bx, -0x10+4(%ebp) # QWordValue[4]
movw %bx, -0x10+6(%ebp) # QWordValue[6]
movq %mm0, -8(%ebp) # Save mm0 to MmxSave
movq -0x10(%ebp), %mm0 # Load QWordValue to mm0
_B:
movq %mm0, %ds:(%edi)
movq %mm0, %ds:8(%edi)
movq %mm0, %ds:16(%edi)
movq %mm0, %ds:24(%edi)
movq %mm0, %ds:32(%edi)
movq %mm0, %ds:40(%edi)
movq %mm0, %ds:48(%edi)
movq %mm0, %ds:56(%edi)
addl $64, %edi
decl %eax
jnz _B
# Restore mm0
movq -8(%ebp), %mm0 # Restore MmxSave to mm0
emms # Exit MMX Instruction
_SetRemindingByte:
movl %edx, %ecx
movl %ebx, %eax
shll $16, %eax
movw %bx, %ax
shrl $2, %ecx
rep
stosl
movl %edx, %ecx
andl $3, %ecx
rep
stosb
popl %ebx
_SetMemDone:
popl %edi
popl %ebx
leave
ret
#EfiCommonLibSetMem ENDP
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